Where do our keys come from?

Roman keys on display

If you’re into escape rooms, you probably love a nice key and padlock. Especially those that are well themed, antique looking and open with that satisfying click! We’re the same, that’s why you will come across a range of examples in our puzzle adventures.

But did you ever stop to think about where keys come from?

The beginnings

Locking mechanisms using keys go back thousands of years. Most scholars assume that they already existed in ancient Egypt, Mesopotamia (modern Iraq), China and probably also other cultures. The problem is that early examples were fashioned from wood. Which is why they generally didn’t survive and we have to rely on written evidence.

Early preserved metal keys come from Greece and have been dated to around the 5th century BCE. Essentially, these took the shape of bent rods that were inserted through a horizontal slit in the door and then moved sideward to shift a bolt on the inside of the door.

A more complex version featured several prongs or teeth at the end bit, but worked basically the same way. This type was still in use in Roman times and you can see some Roman examples in the picture at the very top of the page. The video above gives a little demonstration of how they worked.

Roman upgrades

These simple pronged keys were basic and did not vary much, so the belonging locks could be picked fairly easily and it is likely that one key fitted multiple locks. A safer and more high-tech option were tumbler locks, in which each key prong engaged a tumbler pin of corresponding size and position. The key was slid inside the lock and lifted to engage the tumbler pins, then the deadbolt could be shifted out of the way. In Roman times, this system was greatly improved by creating more complex prong combinations. Additional, the tumblers were equipped with metal springs to ensure their closure (which before was gravity based).

Roman innovation

One of the two biggest key-related inventions that are generally credited to the Romans is the rotary key. Which is  the type of key we now use every day on our front doors! Roman rotary keys have a straight shaft and their bits feature teeth, grooves and/or perforations. They are inserted into a lock-plate and then turned to engage the tumblers or wards, thereby pushing the deadbolt out of the way. You can see some examples of Roman rotary keys in the top row on the picture above.

The Romans also perfected the metallurgical composition, meaning that smaller keys could now be produced. Which led to the introduction of … padlocks! 

It does not seem like a big deal today, but it was a huge step from only being able to lock doors to locking whatever you wanted. And carrying it with you! To suit the new fashion of portable security, the Romans produced key rings. In this case actual rings that were worn on their fingers. What a shame that this fashion did not survive the millennia, I’m sure it’s due a come-back! 

So the upshot of this very brief excursion is…

… let’s add keys and padlocks!!